Serotonin mediates cross-modal reorganization of cortical circuits

Neuron. 2011 Feb 24;69(4):780-92. doi: 10.1016/j.neuron.2011.01.016.

Abstract

Loss of one type of sensory input can cause improved functionality of other sensory systems. Whereas this form of plasticity, cross-modal plasticity, is well established, the molecular and cellular mechanisms underlying it are still unclear. Here, we show that visual deprivation (VD) increases extracellular serotonin in the juvenile rat barrel cortex. This increase in serotonin levels facilitates synaptic strengthening at layer 4 to layer 2/3 synapses within the barrel cortex. Upon VD, whisker experience leads to trafficking of the AMPA-type glutamate receptors (AMPARs) into these synapses through the activation of ERK and increased phosphorylation of AMPAR subunit GluR1 at the juvenile age when natural whisker experience no longer induces synaptic GluR1 delivery. VD thereby leads to sharpening of the functional whisker-barrel map at layer 2/3. Thus, sensory deprivation of one modality leads to serotonin release in remaining modalities, facilitates GluR1-dependent synaptic strengthening, and refines cortical organization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials / physiology
  • Amphetamines / pharmacology
  • Animals
  • Animals, Genetically Modified
  • Animals, Newborn
  • Brain Mapping
  • Cerebral Cortex / cytology*
  • Dopamine / metabolism
  • Extracellular Signal-Regulated MAP Kinases / metabolism
  • Functional Laterality / physiology
  • Green Fluorescent Proteins / genetics
  • Ketanserin / pharmacology
  • Long-Term Potentiation / physiology
  • Male
  • Models, Biological
  • Nerve Net / physiology*
  • Neuronal Plasticity / drug effects
  • Neuronal Plasticity / physiology*
  • Neurons / drug effects
  • Neurons / physiology
  • Phosphorylation / physiology
  • Rats
  • Rats, Long-Evans
  • Receptors, AMPA / genetics
  • Receptors, AMPA / metabolism
  • Sensory Deprivation / physiology
  • Serotonin / metabolism*
  • Serotonin Antagonists / pharmacology
  • Serotonin Receptor Agonists / pharmacology
  • Synapses / drug effects
  • Synapses / physiology
  • Vibrissae / innervation

Substances

  • Amphetamines
  • Receptors, AMPA
  • Serotonin Antagonists
  • Serotonin Receptor Agonists
  • Green Fluorescent Proteins
  • Serotonin
  • Ketanserin
  • Extracellular Signal-Regulated MAP Kinases
  • 4-iodo-2,5-dimethoxyphenylisopropylamine
  • glutamate receptor ionotropic, AMPA 1
  • Dopamine